This invention relates to the field of materials for treating liquid spills.
A problem that is of great environmental concern is the treatment of liquid spills. This is of particular concern when the spill involves harmful, toxic and/or hazardous materials. Such spills must be quickly contained to prevent or minimize the leaching of these materials into the ground and into groundwater supplies. The containment and movement of such liquid spills can be quite costly in the event that the liquid spills must be moved to a Liquid Disposal Site which are typically inaccessible to most sites. The effectiveness of the treatment includes the efficiency, the rate of the treatment and the ability to dispose of the saturated materials used for treatment.
A critical factor in treating such liquid spills is the speed in which the treatment occurs. The longer period of time that elapses while the spill (or aqueous solution) is being cleaned increases the opportunity for the liquid to leach into the surrounding surfaces or to contaminate the environment.
Another problem with such spills is the disposal of the treatment material once the material is fully saturated or the spill has been treated. Most of the prior materials are organic in nature and will often interact with the particular solution being treated. This interaction may cause the contaminate to be re-released back into the environment.
A number of materials are presently utilized in such instances with varying degrees of success. One type of material often used previously has a clay base. This type of material has previously been used for treating oil spills as well as for kitty litter. However these clay-based materials do not work well for many types of spills, they adsorb rather than absorb and tend to deteriorate upon adsorption.
Another popular type of treatment material is cellulose-based, usually in the form of pellets. These materials may be treated to improve absorption but again, are organic based, biodegradable and do not work well for many materials. The contaminates are released back into the environment once these materials begin to degrade.
One prior art attempt at treating water surface pollution is disclosed in U.S. Pat. No. 3,676,357, issued to Ciluti, et al. This patent discloses a composition having a floating carrier, a surface active agent and a wetting agent. This composition is in powder form and is intended for use only in thin laminar oil and gas pollution of bodies of water.
Another prior art attempt is disclosed in U.S. Pat. No. 5,035,804, issued to Stowe. This patent discloses a composition of a fine grained particulate material coated with an oleophilic/hydrophobic layer formed of sulfur, metallic sulfate, an alkali metal nitrate and burned hydrocarbon oil. This material is burned and then used to treat oil spills.
The prior materials used to treat spills are either in powder or pellet form. These materials do not xe2x80x9cbondxe2x80x9d or stick together when dispersed. Thus, when the materials are released, particularly from an elevated position, onto the liquid or solid surface, the materials become airborne and fail to be accurately placed.
This is particularly a problem in environments where small atmospheric particles may contaminate the surrounding environment. For example, enclosed areas such as food processing, food preparation, pharmaceutical manufacturing, computer rooms, printed circuit/wafer manufacturing, and any other enclosed environment where contamination or other interference of airborne particles is of critical concern.
Presently, there are few if any contamination treatment materials that meet the requirements of the United States Food and Drug Administration regulations for use in food preparation and processing environments, including environments where meat, poultry and seafood are collected, processed, packaged and sold. Additionally, few if any liquid spill treatment materials are allowed for use in pharmaceutical manufacturing environments for fear of indirect contamination.
Another area where dispersal of airborne contaminates is of concern includes outdoor environments, such as nuclear or radioactive waste containment and disposal. The lighter weight, non-sticky, particles become easily airborne and subject to wind forces. Not only is the containment of such particles, particularly after the particles have been saturated with a hazardous product, of concern, but their susceptibility to wind forces render them less effective in placement. This reduces their effectiveness as well as raising the costs of treating the spill.
Thus a critical need exists for materials that can quickly and efficiently treat liquid spills for disposal, including liquids having particulates dissolved therein. There is a particular need for materials that can be effectively used without creating atmospheric contamination. There is also a need for materials that can be accurately and efficiently dispersed. There is a further need for materials that can be used under the regulations of the Food and Drug Administration for food preparation and processing environments, pharmaceutical manufacturing and in environments where meat, poultry and seafood are collected, processed, packaged and sold.
The present invention accomplishes those needs by providing an enhanced material capable of quickly, effectively and efficiently treating a variety of liquid spills. In a preferred embodiment of the present invention, the enhanced material uses an inorganic material having specific properties of size and saturability. The material is then treated to increase the adherence of the particles with one another to reduce airborne contamination during dispersal and clean up operations.
In one preferred embodiment, the material includes expanded perlite. This materials has a high porosity due to irregularities formed in the particulates, such as micro-cavities, voids and cracks. In the preferred embodiment, the expanded perlite, amorphous alumina silicate, is used only as particles within a particular range of specifications. In this preferred embodiment, the perlite particles are controlled within specific parameters, having a size range of approximately 297xcexc to 1019xcexc and having saturability properties of between approximately 4.5 liters/Kg to 10.3 liters/Kg. It is to be expressly understood that these ranges are approximate in nature, with expansion on either side of the range to achieve the desired saturation properties of the particles as discussed herein. These properties provide optimum dispersal and saturation properties for treating liquid spills when treated with a petroleum distillate solution, as discussed herein.
In the preferred embodiment, the perlite particles having the size and saturation properties discussed above are treated with a petroleum distillate solution having specific properties as discussed in the detailed description of the preferred embodiments. The petroleum distillate solution is a mixture of non-combustible liquid petroleum hydrocarbons. In the preferred embodiment, the petroleum distillate solution predominantly includes saturated hydrocarbons with some branched, straight chained or saturated cyclic structures. The selected perlite particles are treated with the special mixture of petroleum distillate solution to increase the adherence of the particles together. The selected perlite particles which have been thus treated provide an effective material which can be used without fear of airborne contamination of the surrounding environment and can be effectively and efficiently dispersed on a liquid or surface area to be treated. The treated product will convert the liquid into a moist or semi-dry solid which can be disposed in a Solid Waste Disposal Site rather than the more costly and inaccessible Liquid Waste Disposal Sites.